GM Service Manual Online
For 1990-2009 cars only

Body Control Module (BCM)

Ignition ON/Engine OFF/Vehicle in PARK/Headlamps in AUTO

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Julian Date of Build

Module Information 1

Numeric

Varies

Manufacture Enable Counter

Module Information 1

0-255

0

Module Part Number

Module Information 1

Numeric

Varies

Software Design Suffix

Module Information 1

Two Letters

Varies

Software Part Number

Module Information 1

Numeric

Varies

Lighting Calibration Number

Module Information 2

Numeric

Varies

Lighting Suffix

Module Information 2

Two Letters

Varies

Reminder Calibration Number

Module Information 2

Numeric

Varies

Reminder Suffix

Module Information 2

Two Letters

Varies

Ambient Light

Data

DARK/LIGHT

LIGHT (DRL ON) DARK (AHL ON)

Ambient Light Sensor

Data

Volts

4.7 Volts Maximum Light to 1.0 Volt Maximum Dark

Battery Voltage

Data

Volts

Varies

Courtesy Lamp Timer

Data

Seconds

0 Seconds

Dimming Potentiometer

Data

Volts

Varies

High Beam Input

Data

Volts

12.2 - Low Beams 0.8 - High Beams

Inadvertent Power Timer

Data

Seconds

2400 Seconds

Psgr. Door Jamb/Door Handle Switches

Input 1

ACTIVE/INACTIVE

ACTIVE (door open)

Driver Door Jamb Switch

Input 1

ACTIVE/INACTIVE

ACTIVE (door open)

Ignition 1

Input 1

ACTIVE/INACTIVE

ACTIVE

Ignition 3

Input 1

ACTIVE/INACTIVE

ACTIVE

Ignition Power Mode

Input 1

OFF/RUN/CRANK/ UNKNOWN

RUN

Last Remote Function Actuation Command Since Wake-Up

Input 1

None/Lock/Unlock/Panic/Manual Resynch/Fob Program/Diag Acknowledge/Diag Request

Unlock

Park Brake Switch

Input 1

SET/RELEASED

RELEASED (park brake not set)

Remote Function Actuation Message Since Wake-Up

Input 1

NONE/PANIC/Active Unlock Fob# /Active Lock/Prog Mode Cancel/Prog Successful/Prog Mode Ack/Manual Resync

Actv Unlock Fob#

Auto Headlamps

Input 2

ACTIVE/INACTIVE

INACTIVE (in LIGHT state)

Courtesy Lamp Relay

Input 2

ON/OFF

OFF

Dimming Potentiometer Input

Input 2

ACTIVE/INACTIVE

ACTIVE

Dome Lamp Switch

Input 2

ON/OFF

OFF

Dome Override Switch

Input 2

ON/OFF

OFF

Flash to Pass Switch

Input 2

ON/OFF

OFF

Headlamp Relay Feedback

Input 2

ON/OFF

OFF (in LIGHT state)

High Beam Switch

Input 2

ON/OFF

OFF

Left Turn Signal

Input 2

ON/OFF

OFF

Park Lamps

Input 2

ON/OFF

ON

Right Turn Signal

Input 2

ON/OFF

OFF

Courtesy Lamp Relay

Outputs

ON/OFF

OFF

Daytime Running Lamps Relay

Outputs

ON/OFF

ON (in LIGHT state)

Dimming

Outputs

ACTIVE/INACTIVE

INACTIVE (park lamps OFF)

Headlamp Power Relay

Outputs

ON/OFF

OFF (in LIGHT state)

Inadvertent Power Relay

Outputs

ON/OFF

ON

Interior Lighting Mode

Outputs

None/Interior/Illuminated Entry/Exit Lighting/Remote Illuminated

Interior

Park Lamp Relay

Outputs

ON/OFF

OFF (in LIGHT state)